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Lui S, Brink AK, Corbit LH. Optogenetic stimulation of the locus coeruleus enhances appetitive extinction in rats. eLife 2024; 12:RP89267. [PMID: 38386378 PMCID: PMC10942613 DOI: 10.7554/elife.89267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024] Open
Abstract
Extinction is a specific example of learning where a previously reinforced stimulus or response is no longer reinforced, and the previously learned behaviour is no longer necessary and must be modified. Current theories suggest extinction is not the erasure of the original learning but involves new learning that acts to suppress the original behaviour. Evidence for this can be found when the original behaviour recovers following the passage of time (spontaneous recovery) or reintroduction of the reinforcement (i.e. reinstatement). Recent studies have shown that pharmacological manipulation of noradrenaline (NA) or its receptors can influence appetitive extinction; however, the role and source of endogenous NA in these effects are unknown. Here, we examined the role of the locus coeruleus (LC) in appetitive extinction. Specifically, we tested whether optogenetic stimulation of LC neurons during extinction of a food-seeking behaviour would enhance extinction evidenced by reduced spontaneous recovery in future tests. LC stimulation during extinction trials did not change the rate of extinction but did serve to reduce subsequent spontaneous recovery, suggesting that stimulation of the LC can augment reward-related extinction. Optogenetic inhibition of the LC during extinction trials reduced responding during the trials where it was applied, but no long-lasting changes in the retention of extinction were observed. Since not all LC cells expressed halorhodopsin, it is possible that more complete LC inhibition or pathway-specific targeting would be more effective at suppressing extinction learning. These results provide further insight into the neural basis of appetitive extinction, and in particular the role of the LC. A deeper understanding of the physiological bases of extinction can aid development of more effective extinction-based therapies.
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Affiliation(s)
- Simon Lui
- Department of Psychology, University of TorontoTorontoCanada
| | | | - Laura H Corbit
- Department of Psychology, University of TorontoTorontoCanada
- Cell and Systems Biology, University of TorontoTorontoCanada
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2
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Battaglia S, Di Fazio C, Vicario CM, Avenanti A. Neuropharmacological Modulation of N-methyl-D-aspartate, Noradrenaline and Endocannabinoid Receptors in Fear Extinction Learning: Synaptic Transmission and Plasticity. Int J Mol Sci 2023; 24:ijms24065926. [PMID: 36983000 PMCID: PMC10053024 DOI: 10.3390/ijms24065926] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Learning to recognize and respond to potential threats is crucial for survival. Pavlovian threat conditioning represents a key paradigm for investigating the neurobiological mechanisms of fear learning. In this review, we address the role of specific neuropharmacological adjuvants that act on neurochemical synaptic transmission, as well as on brain plasticity processes implicated in fear memory. We focus on novel neuropharmacological manipulations targeting glutamatergic, noradrenergic, and endocannabinoid systems, and address how the modulation of these neurobiological systems affects fear extinction learning in humans. We show that the administration of N-methyl-D-aspartate (NMDA) agonists and modulation of the endocannabinoid system by fatty acid amide hydrolase (FAAH) inhibition can boost extinction learning through the stabilization and regulation of the receptor concentration. On the other hand, elevated noradrenaline levels dynamically modulate fear learning, hindering long-term extinction processes. These pharmacological interventions could provide novel targeted treatments and prevention strategies for fear-based and anxiety-related disorders.
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Affiliation(s)
- Simone Battaglia
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", Cesena Campus, Alma Mater Studiorum Università di Bologna, 47521 Cesena, Italy
- Department of Psychology, University of Turin, 10124 Turin, Italy
| | - Chiara Di Fazio
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", Cesena Campus, Alma Mater Studiorum Università di Bologna, 47521 Cesena, Italy
| | - Carmelo M Vicario
- Dipartimento di Scienze Cognitive, Psicologiche, Pedagogiche e Degli Studi Culturali, Università Degli Studi di Messina, 98122 Messina, Italy
| | - Alessio Avenanti
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", Cesena Campus, Alma Mater Studiorum Università di Bologna, 47521 Cesena, Italy
- Neuropsicology and Cognitive Neuroscience Research Center (CINPSI Neurocog), Universidad Católica del Maule, Talca 3460000, Chile
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3
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Faraji N, Meftahi GH, Shiravi A, Bahari Z. Evaluation of the effects of phenylephrine and prazosin injection into basolateral amygdala on the post-stress experience of memory retrieval in rats. LEARNING AND MOTIVATION 2023. [DOI: 10.1016/j.lmot.2022.101868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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4
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Huang J, Xu F, Yang L, Tuolihong L, Wang X, Du Z, Zhang Y, Yin X, Li Y, Lu K, Wang W. Involvement of the GABAergic system in PTSD and its therapeutic significance. Front Mol Neurosci 2023; 16:1052288. [PMID: 36818657 PMCID: PMC9928765 DOI: 10.3389/fnmol.2023.1052288] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 01/16/2023] [Indexed: 02/04/2023] Open
Abstract
The neurobiological mechanism of post-traumatic stress disorder (PTSD) is poorly understood. The inhibition of GABA neurons, especially in the amygdala, is crucial for the precise regulation of the consolidation, expression, and extinction of fear conditioning. The GABAergic system is involved in the pathophysiological process of PTSD, with several studies demonstrating that the function of the GABAergic system decreases in PTSD patients. This paper reviews the preclinical and clinical studies, neuroimaging techniques, and pharmacological studies of the GABAergic system in PTSD and summarizes the role of the GABAergic system in PTSD. Understanding the role of the GABAergic system in PTSD and searching for new drug targets will be helpful in the treatment of PTSD.
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Affiliation(s)
| | - Fei Xu
- Department of Psychiatry of School of Public Health, Southern Medical University, Guangzhou, China
| | - Liping Yang
- Department of Applied Psychology of School of Public Health, Southern Medical University, Guangzhou, China
| | - Lina Tuolihong
- Department of Basic Medical of Basic Medical College, Southern Medical University, Guangzhou, China
| | - Xiaoyu Wang
- Eight-Year Master's and Doctoral Program in Clinical Medicine of the First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Zibo Du
- Eight-Year Master's and Doctoral Program in Clinical Medicine of the First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Yiqi Zhang
- Eight-Year Master's and Doctoral Program in Clinical Medicine of the First Clinical Medical College, Southern Medical University, Guangzhou, China
| | - Xuanlin Yin
- Department of Basic Medical of Basic Medical College, Southern Medical University, Guangzhou, China
| | - Yingjun Li
- Department of Medical Laboratory Science, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Kangrong Lu
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Southern Medical University, Guangzhou, China
| | - Wanshan Wang
- Department of Laboratory Animal Center, Southern Medical University, Guangzhou, China
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5
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Forte G, Favieri F, Leemhuis E, De Martino ML, Giannini AM, De Gennaro L, Casagrande M, Pazzaglia M. Ear your heart: transcutaneous auricular vagus nerve stimulation on heart rate variability in healthy young participants. PeerJ 2022; 10:e14447. [PMID: 36438582 PMCID: PMC9686410 DOI: 10.7717/peerj.14447] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 11/01/2022] [Indexed: 11/22/2022] Open
Abstract
Background Transcutaneous auricular vagus nerve stimulation (taVNS) stimulating the auricular branch of the vagus nerve along a well-defined neuroanatomical pathway, has promising therapeutic efficacy. Potentially, taVNS can modulate autonomic responses. Specifically, taVNS can induce more consistent parasympathetic activation and may lead to increased heart rate variability (HRV). However, the effects of taVNS on HRV remain inconclusive. Here, we investigated changes in HRV due to brief alteration periods of parasympathetic-vagal cardiac activity produced by taVNS on the cymba as opposed to control administration via the helix. Materials and Methods We compared the effect of 10 min of active stimulation (i.e., cymba conchae) to sham stimulation (i.e., helix) on peripheral cardiovascular response, in 28 healthy young adults. HRV was estimated in the time domain and frequency domain during the overall stimulation. Results Although active-taVNS and sham-taVNS stimulation did not differ in subjective intensity ratings, the active stimulation of the cymba led to vagally mediated HRV increases in both the time and frequency domains. Differences were significant between active-taVNS and both sham-taVNS and resting conditions in the absence of stimulation for various HRV parameters, but not for the low-frequency index of HRV, where no differences were found between active-taVNS and sham-taVNS conditions. Conclusion This work supports the hypothesis that taVNS reliably induces a rapid increase in HRV parameters when auricular stimulation is used to recruit fibers in the cymba compared to stimulation at another site. The results suggest that HRV can be used as a physiological indicator of autonomic tone in taVNS for research and potential therapeutic applications, in line with the established effects of invasive VNS. Knowledge of the physiological effect of taVNS short sessions in modulating cardiovagal processing is essential for enhancing its clinical use.
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Affiliation(s)
- Giuseppe Forte
- Body and Action Lab, IRCCS Fondazione Santa Lucia, Rome, Italy,Department of Psychology, University of Roma “La Sapienza”, Rome, Italy
| | - Francesca Favieri
- Body and Action Lab, IRCCS Fondazione Santa Lucia, Rome, Italy,Department of Psychology, University of Roma “La Sapienza”, Rome, Italy
| | - Erik Leemhuis
- Body and Action Lab, IRCCS Fondazione Santa Lucia, Rome, Italy,Department of Psychology, University of Roma “La Sapienza”, Rome, Italy
| | - Maria Luisa De Martino
- Body and Action Lab, IRCCS Fondazione Santa Lucia, Rome, Italy,Department of Psychology, University of Roma “La Sapienza”, Rome, Italy
| | | | - Luigi De Gennaro
- Body and Action Lab, IRCCS Fondazione Santa Lucia, Rome, Italy,Department of Psychology, University of Roma “La Sapienza”, Rome, Italy
| | - Maria Casagrande
- Dipartimento di Psicologia Clinica, Dinamica e Salute, University of Roma “La Sapienza”, Rome, Italy
| | - Mariella Pazzaglia
- Body and Action Lab, IRCCS Fondazione Santa Lucia, Rome, Italy,Department of Psychology, University of Roma “La Sapienza”, Rome, Italy
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Role of noradrenergic arousal for fear extinction processes in rodents and humans. Neurobiol Learn Mem 2022; 194:107660. [PMID: 35870717 DOI: 10.1016/j.nlm.2022.107660] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/29/2022] [Accepted: 07/17/2022] [Indexed: 01/22/2023]
Abstract
Fear extinction is a learning mechanism that is pivotal for the inhibition of fear responses towards cues or contexts that no longer predict the occurrence of a threat. Failure of fear extinction leads to fear expression under safe conditions and is regarded to be a cardinal characteristic of many anxiety-related disorders and posttraumatic stress disorder. Importantly, the neurotransmitter noradrenaline was shown to be a potent modulator of fear extinction. Rodent studies demonstrated that excessive noradrenaline transmission after acute stress opens a time window of vulnerability, in which fear extinction learning results in attenuated long-term extinction success. In contrast, when excessive noradrenergic transmission subsides, well-coordinated noradrenaline transmission is necessary for the formation of a long-lasting extinction memory. In addition, emerging evidence suggests that the neuropeptide corticotropin releasing hormone (CRF), which strongly regulates noradrenaline transmission under conditions of acute stress, also impedes long-term extinction success. Recent rodent work - using sophisticated methods - provides evidence for a hypothetical mechanistic framework of how noradrenaline and CRF dynamically orchestrate the neural fear and extinction circuitry to attenuate or to improve fear extinction and extinction recall. Accordingly, we review the evidence from rodent studies linking noradrenaline and CRF to fear extinction learning and recall and derive the hypothetical mechanistic framework of how different levels of noradrenaline and CRF may create a time window of vulnerability which impedes successful long-term fear extinction. We also address evidence from human studies linking noradrenaline and fear extinction success. Moreover, we accumulate emerging approaches to non-invasively measure and manipulate the noradrenergic system in healthy humans. Finally, we emphasize the importance of future studies to account for sex (hormone) differences when examining the interaction between fear extinction, noradrenaline, and CRF. To conclude, NA's effects on fear extinction recall strongly depend on the arousal levels at the onset of fear extinction learning. Our review aimed at compiling the available (mainly rodent) data in a neurobiological framework, suited to derive testable hypotheses for future work in humans.
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7
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Raut SB, Marathe PA, van Eijk L, Eri R, Ravindran M, Benedek DM, Ursano RJ, Canales JJ, Johnson LR. Diverse therapeutic developments for post-traumatic stress disorder (PTSD) indicate common mechanisms of memory modulation. Pharmacol Ther 2022; 239:108195. [PMID: 35489438 DOI: 10.1016/j.pharmthera.2022.108195] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 12/20/2022]
Abstract
Post-traumatic stress disorder (PTSD), characterized by abnormally persistent and distressing memories, is a chronic debilitating condition in need of new treatment options. Current treatment guidelines recommend psychotherapy as first line management with only two drugs, sertraline and paroxetine, approved by U.S. Food and Drug Administration (FDA) for treatment of PTSD. These drugs have limited efficacy as they only reduce symptoms related to depression and anxiety without producing permanent remission. PTSD remains a significant public health problem with high morbidity and mortality requiring major advances in therapeutics. Early evidence has emerged for the beneficial effects of psychedelics particularly in combination with psychotherapy for management of PTSD, including psilocybin, MDMA, LSD, cannabinoids, ayahuasca and ketamine. MDMA and psilocybin reduce barrier to therapy by increasing trust between therapist and patient, thus allowing for modification of trauma related memories. Furthermore, research into the memory reconsolidation mechanisms has allowed for identification of various pharmacological targets to disrupt abnormally persistent memories. A number of pre-clinical and clinical studies have investigated novel and re-purposed pharmacological agents to disrupt fear memory in PTSD. Novel therapeutic approaches like neuropeptide Y, oxytocin, cannabinoids and neuroactive steroids have also shown potential for PTSD treatment. Here, we focus on the role of fear memory in the pathophysiology of PTSD and propose that many of these new therapeutic strategies produce benefits through the effect on fear memory. Evaluation of recent research findings suggests that while a number of drugs have shown promising results in preclinical studies and pilot clinical trials, the evidence from large scale clinical trials would be needed for these drugs to be incorporated in clinical practice.
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Affiliation(s)
- Sanket B Raut
- Schools of Psychological Sciences, College of Health and Medicine, University of Tasmania, TAS 7250, Australia
| | - Padmaja A Marathe
- Department of Pharmacology and Therapeutics, Seth GS Medical College & KEM Hospital, Parel, Mumbai 400 012, India
| | - Liza van Eijk
- Department of Psychology, College of Healthcare Sciences, James Cook University, QLD 4811, Australia
| | - Rajaraman Eri
- Health Sciences, College of Health and Medicine, University of Tasmania, TAS 7250, Australia
| | - Manoj Ravindran
- Medicine, College of Health and Medicine, University of Tasmania, TAS 7250, Australia; Department of Psychiatry, North-West Private Hospital, Burnie TAS 7320, Australia
| | - David M Benedek
- Centre for the Study of Traumatic Stress, Department of Psychiatry, Uniformed Services University School of Medicine, Bethesda, MD 20814, USA
| | - Robert J Ursano
- Centre for the Study of Traumatic Stress, Department of Psychiatry, Uniformed Services University School of Medicine, Bethesda, MD 20814, USA
| | - Juan J Canales
- Schools of Psychological Sciences, College of Health and Medicine, University of Tasmania, TAS 7250, Australia
| | - Luke R Johnson
- Schools of Psychological Sciences, College of Health and Medicine, University of Tasmania, TAS 7250, Australia; Centre for the Study of Traumatic Stress, Department of Psychiatry, Uniformed Services University School of Medicine, Bethesda, MD 20814, USA.
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8
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Feinstein D. Uses of Energy Psychology Following Catastrophic Events. Front Psychol 2022; 13:856209. [PMID: 35548526 PMCID: PMC9084314 DOI: 10.3389/fpsyg.2022.856209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 02/14/2022] [Indexed: 12/15/2022] Open
Abstract
Energy psychology, as most widely practiced, integrates the manual stimulation of acupuncture points with imaginal exposure, cognitive restructuring, and other evidence-based psychotherapeutic procedures. Efficacy for energy psychology protocols has been established in more than 120 clinical trials, with meta-analyses showing strong effect sizes for PTSD, anxiety, and depression. The approach has been applied in the wake of natural and human-made disasters in more than 30 countries. Four tiers of energy psychology interventions following the establishment of safety, trust, and rapport are described, including (1) immediate relief/stabilization, (2) reducing limbic arousal to trauma-based triggers, (3) overcoming complex psychological difficulties, and (4) promoting optimal functioning. The first tier is most pertinent in psychological first aid immediately following a disaster, with the subsequent tiers progressively being introduced over time with complex stress reactions and chronic disorders. Advantages of adding the stimulation of acupuncture points to a conventional exposure approach are identified, and challenges around cultural sensitivities and unintended effects are discussed. After establishing a framework for introducing energy psychology in disaster relief efforts, reports from a sampling of settings are presented, based on interviews with this paper's author. These include accounts of relief work with survivors of mass shootings, genocide, ethnic warfare, earthquakes, hurricanes, tornadoes, floods, wildfires, and the COVID-19 pandemic. Hundreds of other reports from the field show a pattern of strong outcomes following the use of energy psychology in the days or weeks after a disaster and in the subsequent treatment of trauma-based psychological problems. Many of these accounts corroborate one another in terms of rapid relief and long-term benefits. Finally, examples of more efficient delivery methods utilizing large groups, lay counselors, digital technology, and cultivating community resilience are presented.
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9
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Schaan Fernandes H, Popik B, de Oliveira Alvares L. Effects of hippocampal IP 3R inhibition on contextual fear memory consolidation, retrieval, reconsolidation and extinction. Neurobiol Learn Mem 2022; 188:107587. [PMID: 35051621 DOI: 10.1016/j.nlm.2022.107587] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/03/2022] [Accepted: 01/12/2022] [Indexed: 10/19/2022]
Abstract
Intracellular calcium stores (ICS) play a dynamic role in neuronal calcium (Ca2+) homeostasis both by buffering Ca2+ excess in the cytoplasm or providing an additional source of Ca2+ when concentration increase is needed. However, in spite of the large body of evidence showing Ca2+ as an essential second messenger in many signaling cascades underlying synaptic plasticity, the direct involvement of the intracellular Ca2+-release channels (ICRCs) in memory processing has been highly overlooked. Here we investigated the role of the ICRC inositol 1,4,5-trisphosphate receptor (IP3R) activity during different memory phases using pharmacological inhibition in the dorsal hippocampus during contextual fear conditioning. We first found that post-training administration of the IP3R antagonist 2-aminoethyl diphenylborinate (2-APB) impaired memory consolidation in a dose and time-dependent manner. Inhibiting IP3Rs also disrupted memory retrieval. Contextual fear memory reconsolidation or extinction, however, were not sensitive to IP3R blockade. Taken together, our results indicate that hippocampal IP3Rs play an important role in contextual fear memory consolidation and retrieval.
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Affiliation(s)
- Henrique Schaan Fernandes
- Laboratório de Neurobiologia da Memória, Biophysics Department, Biosciences Institute, Federal University of Rio Grande do Sul, 91,501-970 Porto Alegre, Brazil; Graduate Program in Neuroscience, Institute of Health Sciences, Federal University of Rio Grande do Sul, 90,046-900 Porto Alegre, Brazil
| | - Bruno Popik
- Laboratório de Neurobiologia da Memória, Biophysics Department, Biosciences Institute, Federal University of Rio Grande do Sul, 91,501-970 Porto Alegre, Brazil; Graduate Program in Neuroscience, Institute of Health Sciences, Federal University of Rio Grande do Sul, 90,046-900 Porto Alegre, Brazil
| | - Lucas de Oliveira Alvares
- Laboratório de Neurobiologia da Memória, Biophysics Department, Biosciences Institute, Federal University of Rio Grande do Sul, 91,501-970 Porto Alegre, Brazil; Graduate Program in Neuroscience, Institute of Health Sciences, Federal University of Rio Grande do Sul, 90,046-900 Porto Alegre, Brazil.
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10
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Meyer HC, Sangha S, Radley JJ, LaLumiere RT, Baratta MV. Environmental certainty influences the neural systems regulating responses to threat and stress. Neurosci Biobehav Rev 2021; 131:1037-1055. [PMID: 34673111 PMCID: PMC8642312 DOI: 10.1016/j.neubiorev.2021.10.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Abstract
Flexible calibration of threat responding in accordance with the environment is an adaptive process that allows an animal to avoid harm while also maintaining engagement of other goal-directed actions. This calibration process, referred to as threat response regulation, requires an animal to calculate the probability that a given encounter will result in a threat so they can respond accordingly. Here we review the neural correlates of two highly studied forms of threat response suppression: extinction and safety conditioning. We focus on how relative levels of certainty or uncertainty in the surrounding environment alter the acquisition and application of these processes. We also discuss evidence indicating altered threat response regulation following stress exposure, including enhanced fear conditioning, and disrupted extinction and safety conditioning. To conclude, we discuss research using an animal model of coping that examines the impact of stressor controllability on threat responding, highlighting the potential for previous experiences with control, or other forms of coping, to protect against the effects of future adversity.
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Affiliation(s)
- Heidi C Meyer
- Department of Psychological and Brain Sciences, Boston University, Boston, MA, 02215, USA.
| | - Susan Sangha
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA.
| | - Jason J Radley
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, 52242, USA.
| | - Ryan T LaLumiere
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, 52242, USA.
| | - Michael V Baratta
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, 80301, USA.
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11
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Baldi E, Costa A, Rani B, Passani MB, Blandina P, Romano A, Provensi G. Oxytocin and Fear Memory Extinction: Possible Implications for the Therapy of Fear Disorders? Int J Mol Sci 2021; 22:10000. [PMID: 34576161 PMCID: PMC8467761 DOI: 10.3390/ijms221810000] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/07/2021] [Accepted: 09/10/2021] [Indexed: 02/07/2023] Open
Abstract
Several psychiatric conditions such as phobias, generalized anxiety, and post-traumatic stress disorder (PTSD) are characterized by pathological fear and anxiety. The main therapeutic approach used in the management of these disorders is exposure-based therapy, which is conceptually based upon fear extinction with the formation of a new safe memory association, allowing the reduction in behavioral conditioned fear responses. Nevertheless, this approach is only partially resolutive, since many patients have difficulty following the demanding and long process, and relapses are frequently observed over time. One strategy to improve the efficacy of the cognitive therapy is the combination with pharmacological agents. Therefore, the identification of compounds able to strengthen the formation and persistence of the inhibitory associations is a key goal. Recently, growing interest has been aroused by the neuropeptide oxytocin (OXT), which has been shown to have anxiolytic effects. Furthermore, OXT receptors and binding sites have been found in the critical brain structures involved in fear extinction. In this review, the recent literature addressing the complex effects of OXT on fear extinction at preclinical and clinical levels is discussed. These studies suggest that the OXT roles in fear behavior are due to its local effects in several brain regions, most notably, distinct amygdaloid regions.
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Affiliation(s)
- Elisabetta Baldi
- Section of Physiological Sciences, Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy;
| | - Alessia Costa
- Section of Clinical Pharmacology and Oncology, Department of Health Sciences (DSS), University of Florence, 50139 Florence, Italy; (A.C.); (B.R.); (M.B.P.)
| | - Barbara Rani
- Section of Clinical Pharmacology and Oncology, Department of Health Sciences (DSS), University of Florence, 50139 Florence, Italy; (A.C.); (B.R.); (M.B.P.)
| | - Maria Beatrice Passani
- Section of Clinical Pharmacology and Oncology, Department of Health Sciences (DSS), University of Florence, 50139 Florence, Italy; (A.C.); (B.R.); (M.B.P.)
| | - Patrizio Blandina
- Section of Pharmacology of Toxicology, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, 50139 Florence, Italy;
| | - Adele Romano
- Department of Physiology and Pharmacology ‘V. Erspamer’, Sapienza University of Rome, 00185 Rome, Italy;
| | - Gustavo Provensi
- Section of Pharmacology of Toxicology, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, 50139 Florence, Italy;
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12
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Zhou Y, Wang W, Liu Y, Xie L, Tang Y. The Effect of Noise on the Neurobehavioral Function of the Occupational Population and the Content of Catecholamines. J Occup Environ Med 2021; 63:e641-e649. [PMID: 34491972 DOI: 10.1097/jom.0000000000002320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
According to the decibel level of noise detection in the working environment, the research objects were divided into high noise group (more than 85 dB), low noise group (55 to 85 dB), and control group (less than 55 dB), the neurobehavioral core test battery (NCTB) was used to systematic tests all workers, radioimmunoassay was used to detect plasma catecholamine levels, and the relationship between noise intensities and the levels of plasma catecholamine was analyzed by canonical correlation. The result shows noise exposure will affect workers' neurological function and the influence of noise on neurobehavioral function may be related to the increase of the levels of norepinephrine and dopamine in the plasma and the inhibition of the synthesis of epinephrine of noise-exposed workers.
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Affiliation(s)
- Yu Zhou
- Department of Public Health (Ms Zhou, Mr Xie, Mrs Liu); Yibin City Center for Disease Control and Prevention, Yibin Province, China (Mr Wang); Public Health Experimental Center of Southwest Medical University (Mr Tang), Southwest Medical University, Luzhou, SiChuan Province, China
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13
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Iordanova MD, Yau JOY, McDannald MA, Corbit LH. Neural substrates of appetitive and aversive prediction error. Neurosci Biobehav Rev 2021; 123:337-351. [PMID: 33453307 PMCID: PMC7933120 DOI: 10.1016/j.neubiorev.2020.10.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/24/2020] [Accepted: 10/13/2020] [Indexed: 12/14/2022]
Abstract
Prediction error, defined by the discrepancy between real and expected outcomes, lies at the core of associative learning. Behavioural investigations have provided evidence that prediction error up- and down-regulates associative relationships, and allocates attention to stimuli to enable learning. These behavioural advances have recently been followed by investigations into the neurobiological substrates of prediction error. In the present paper, we review neuroscience data obtained using causal and recording neural methods from a variety of key behavioural designs. We explore the neurobiology of both appetitive (reward) and aversive (fear) prediction error with a focus on the mesolimbic dopamine system, the amygdala, ventrolateral periaqueductal gray, hippocampus, cortex and locus coeruleus noradrenaline. New questions and avenues for research are considered.
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Affiliation(s)
- Mihaela D Iordanova
- Department of Psychology/Centre for Studies in Behavioral Neurobiology, Concordia University, 7141 Sherbrooke St, Montreal, QC, H4B 1R6, Canada.
| | - Joanna Oi-Yue Yau
- School of Psychology, The University of New South Wales, UNSW Sydney, NSW, 2052, Australia.
| | - Michael A McDannald
- Department of Psychology & Neuroscience, Boston College, 140 Commonwealth Avenue, 514 McGuinn Hall, Chestnut Hill, MA, 02467, USA.
| | - Laura H Corbit
- Departments of Psychology and Cell and Systems Biology, University of Toronto, 100 St. George Street, Toronto, ON, M5S 3G3, Canada.
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14
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Warren WG, Papagianni EP, Stevenson CW, Stubbendorff C. In it together? The case for endocannabinoid-noradrenergic interactions in fear extinction. Eur J Neurosci 2021; 55:952-970. [PMID: 33759226 DOI: 10.1111/ejn.15200] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 01/26/2021] [Accepted: 03/17/2021] [Indexed: 12/18/2022]
Abstract
Anxiety and trauma-related disorders, such as post-traumatic stress disorder (PTSD), are debilitating mental illnesses with great personal and socioeconomic costs. Examining memory formation and relevant behavioural responding associated with aversive stimuli may improve our understanding of the neurobiology underlying fear memory processing and PTSD treatment. The neurocircuitry underpinning learned fear and its inhibition through extinction is complex, involving synergistic interactions between different neurotransmitter systems in inter-connected brain areas. Endocannabinoid and noradrenergic transmission have both been implicated separately in fear memory processing and PTSD, but potential interactions between these systems in relation to fear extinction have received little attention to date. Their receptors are expressed together in brain areas crucial for fear extinction, which is enhanced by both cannabinoid and noradrenergic receptor activation in these areas. Moreover, cannabinoid signalling modulates the activity of locus coeruleus noradrenaline (NA) neurons and the release of NA in the medial prefrontal cortex, a brain area that is crucial for fear extinction. Interestingly, endocannabinoid-noradrenergic system interactions have been shown to regulate the encoding and retrieval of fear memory. Thus, noradrenergic regulation of fear extinction may also be driven indirectly in part via cannabinoid receptor signalling. In this perspective paper, we collate the available relevant literature and propose a synergistic role for the endocannabinoid and noradrenergic systems in regulating fear extinction, the study of which may further our understanding of the neurobiological substrates of PTSD and its treatment.
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Affiliation(s)
- William G Warren
- School of Biosciences, University of Nottingham, Loughborough, UK
| | | | - Carl W Stevenson
- School of Biosciences, University of Nottingham, Loughborough, UK
| | - Christine Stubbendorff
- School of Biosciences, University of Nottingham, Loughborough, UK.,Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
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15
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Souza RR, Oleksiak CR, Tabet MN, Rennaker RL, Hays SA, Kilgard MP, McIntyre CK. Vagus nerve stimulation promotes extinction generalization across sensory modalities. Neurobiol Learn Mem 2021; 181:107425. [PMID: 33771710 DOI: 10.1016/j.nlm.2021.107425] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/12/2021] [Accepted: 03/19/2021] [Indexed: 11/29/2022]
Abstract
Traumatic experiences involve complex sensory information, and individuals with trauma-related psychological disorders, such as posttraumatic stress disorder (PTSD), can exhibit abnormal fear to numerous different stimuli that remind them of the trauma. Vagus nerve stimulation (VNS) enhances extinction of auditory fear conditioning in rat models for PTSD. We recently found that VNS-paired extinction can also promote extinction generalization across different auditory cues. Here we tested whether VNS can enhance extinction of olfactory fear and promote extinction generalization across auditory and olfactory sensory modalities. Male Sprague Dawley rats were implanted with a stimulating cuff on the cervical vagus nerve. Rats then received two days of fear conditioning where olfactory (amyl acetate odor) and auditory (9 kHz tones) stimuli were concomitantly paired with footshock. Twenty-four hours later, rats were given three days of sham or VNS-paired extinction (5 stimulations, 30-sec trains at 0.4 mA) overlapping with presentation of either the olfactory or the auditory stimulus. Two days later, rats were given an extinction retention test where avoidance of the olfactory stimulus or freezing to the auditory stimulus were measured. VNS-paired with exposure to the olfactory stimulus during extinction reduced avoidance of the odor in the retention test. VNS-paired with exposure to the auditory stimulus during extinction also decreased avoidance of the olfactory cue, and VNS paired with exposure to the olfactory stimulus during extinction reduced freezing when the auditory stimulus was presented in the retention test. These results indicate that VNS enhances extinction of olfactory fear and promotes extinction generalization across different sensory modalities. Extinction generalization induced by VNS may therefore improve outcomes of exposure-based therapies.
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Affiliation(s)
- Rimenez R Souza
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
| | - Cecily R Oleksiak
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
| | - Michel N Tabet
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
| | - Robert L Rennaker
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
| | - Seth A Hays
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
| | - Michael P Kilgard
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
| | - Christa K McIntyre
- Texas Biomedical Device Center, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States; School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, United States
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16
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Understanding the dynamic and destiny of memories. Neurosci Biobehav Rev 2021; 125:592-607. [PMID: 33722616 DOI: 10.1016/j.neubiorev.2021.03.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 01/18/2021] [Accepted: 03/08/2021] [Indexed: 01/16/2023]
Abstract
Memory formation enables the retention of life experiences overtime. Based on previously acquired information, organisms can anticipate future events and adjust their behaviors to maximize survival. However, in an ever-changing environment, a memory needs to be malleable to maintain its relevance. In fact, substantial evidence suggests that a consolidated memory can become labile and susceptible to modifications after being reactivated, a process termed reconsolidation. When an extinction process takes place, a memory can also be temporarily inhibited by a second memory that carries information with opposite meaning. In addition, a memory can fade and lose its significance in a process known as forgetting. Thus, following retrieval, new life experiences can be integrated with the original memory trace to maintain its predictive value. In this review, we explore the determining factors that regulate the fate of a memory after its reactivation. We focus on three post-retrieval memory destinies (reconsolidation, extinction, and forgetting) and discuss recent rodent studies investigating the biological functions and neural mechanisms underlying each of these processes.
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17
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Preventing dementia? Interventional approaches in mild cognitive impairment. Neurosci Biobehav Rev 2021; 122:143-164. [PMID: 33440197 DOI: 10.1016/j.neubiorev.2020.12.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 10/13/2020] [Accepted: 12/19/2020] [Indexed: 12/19/2022]
Abstract
Mild cognitive impairment (MCI) is defined as an intermediate state between normal cognitive aging and dementia. It describes a status of the subjective impression of cognitive decline and objectively detectible memory impairment beyond normal age-related changes. Activities of daily living are not affected. As the population ages, there is a growing need for early, proactive programs that can delay the consequences of dementia and improve the well-being of people with MCI and their caregivers. Various forms and approaches of intervention for older people with MCI have been suggested to delay cognitive decline. Pharmacological as well as non-pharmacological approaches (cognitive, physiological, nutritional supplementation, electric stimulation, psychosocial therapeutic) and multicomponent interventions have been proposed. Interventional approaches in MCI from 2009 to April 2019 concerning the cognitive performance are presented in this review.
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18
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Seo JH, Kim TY, Kim SJ, Choi JH, So HS, Kang JI. Possible Association of Polymorphisms in Ubiquitin Specific Peptidase 46 Gene With Post-traumatic Stress Disorder. Front Psychiatry 2021; 12:663647. [PMID: 34456759 PMCID: PMC8385240 DOI: 10.3389/fpsyt.2021.663647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 07/14/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: Dynamic proteolysis, through the ubiquitin-proteasome system, has an important role in DNA transcription and cell cycle, and is considered to modulate cell stress response and synaptic plasticity. We investigated whether genetic variants in the ubiquitin carboxyl-terminal hydrolase 46 (USP46) would be associated with post-traumatic stress disorder (PTSD) in people with exposure to combat trauma using a case-control candidate gene association design. Methods: Korean male veterans exposed to the Vietnam War were grouped into those with (n = 128) and without (n = 128) PTSD. Seven tagging SNPs of USP46 were selected, and single-marker and haplotype-based association analyses were performed. All analyses were adjusted for sociodemographic factors and levels of combat exposure severity and alcohol problem. Results: One single-marker (rs2244291) showed nominal evidence of association with PTSD status and with the "re-experiencing" cluster, although the association was not significant after Bonferroni correction. No significant association with the other SNPs or the haplotypes was detected. Conclusion: The present finding suggests preliminarily that genetic vulnerability regarding the ubiquitin-proteasome system may be related to fear memory processes and the development of PTSD symptoms after trauma exposure. Further studies with a larger sample size will be needed to examine the role of the ubiquitin-proteasome system including USP46 in PTSD.
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Affiliation(s)
- Jun Ho Seo
- Institute of Behavioral Science in Medicine and Department of Psychiatry, Yonsei University College of Medicine, Seoul, South Korea
| | - Tae Yong Kim
- Institute of Behavioral Science in Medicine and Department of Psychiatry, Yonsei University College of Medicine, Seoul, South Korea.,Department of Neuropsychiatry, Veterans Health Service Medical Center, Seoul, South Korea
| | - Se Joo Kim
- Institute of Behavioral Science in Medicine and Department of Psychiatry, Yonsei University College of Medicine, Seoul, South Korea
| | - Jin Hee Choi
- Department of Neuropsychiatry, Veterans Health Service Medical Center, Seoul, South Korea
| | - Hyung Seok So
- Department of Neuropsychiatry, Veterans Health Service Medical Center, Seoul, South Korea
| | - Jee In Kang
- Institute of Behavioral Science in Medicine and Department of Psychiatry, Yonsei University College of Medicine, Seoul, South Korea
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19
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Cavalcante KM, Bispo JM, Souza MF, Medeiros KA, Lins LC, Santos ER, Melo JE, Gois AM, Meurer YS, Leal PC, Marchioro M, Santos JR. Short-term but not long-term exposure to an enriched environment facilitates the extinction of aversive memory. Behav Brain Res 2020; 393:112806. [DOI: 10.1016/j.bbr.2020.112806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 06/26/2020] [Accepted: 07/08/2020] [Indexed: 10/23/2022]
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20
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Li Y, Li X, Xie M, Cheng L, Chen H, Sun H, Jiang L. [Toxicity of dibutyl phthalate in primary cultured rat hippocampal neurons and the toxicological mechanism]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2020; 40:225-232. [PMID: 32376539 DOI: 10.12122/j.issn.1673-4254.2020.02.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the neurotoxicity and toxicological mechanism of dibutyl phthalate (DBP) in primary cultured rat hippocampal neurons. METHODS Primary rat hippocampal neurons cultured for 4 days were exposed to 1 g/L DBP for 24, 48, or 96 h. Immunofluorescence assay and transmission electron microscopy (TEM) were used to observe the morphological changes of the axons and the ultrastructure of DBP-treated neurons. The action potential (AP) of the hippocampal neurons was measured with patch-clamp electrophysiology. CCK-8 assay was used to detect the viability of the hippocampal neurons, and Western blotting was performed to determine the mRNA and protein expressions of brain-derived neurotrophic factor (BDNF), neuropeptide Y (NPY) and estrogen receptor β (ERβ). High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS) was employed to detect the release of the neurotransmitter GABA. RESULTS After exposure to DBP for 96 h, the cellular network of the hippocampal neurons became sparse, and the neurons showed significantly decreased axonal length (P < 0.01) and presented with round cell nuclei, chromatin aggregation and cytoplasmic vacuolization. Patch-clamp electrophysiology revealed depolarization drift and increased frequency of discharge in the exposed neurons (P < 0.01). The neurons with DBP exposure for 24, 48 and 96 h all showed significantly decreased cell viability (P < 0.01). DBP exposure for 48 and 96 h significantly lowered the protein expressions of ERβ, BDNF and NPY, and a 96-h exposure significantly reduced the release of the neurotransmitter GABA in the neurons (P < 0.05). CONCLUSIONS DBP exposure causes morphological and functional damages of primary cultured rat hippocampal neurons. DBP-induced neurotoxicity is probably associated with GABA-mediated blockage of the ERβ-BDNF-NPY signaling communication.
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Affiliation(s)
- Yang Li
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Xiujuan Li
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China.,Ministry of Education Key Laboratory of Child Development and Disorders/National Clinical Research Center for Child Health and Disorders/China International Science and Technology Cooperation Base of Child Development and Critical Disorders/Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Mingdan Xie
- Ministry of Education Key Laboratory of Child Development and Disorders/National Clinical Research Center for Child Health and Disorders/China International Science and Technology Cooperation Base of Child Development and Critical Disorders/Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Li Cheng
- Ministry of Education Key Laboratory of Child Development and Disorders/National Clinical Research Center for Child Health and Disorders/China International Science and Technology Cooperation Base of Child Development and Critical Disorders/Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Hengsheng Chen
- Ministry of Education Key Laboratory of Child Development and Disorders/National Clinical Research Center for Child Health and Disorders/China International Science and Technology Cooperation Base of Child Development and Critical Disorders/Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Hong Sun
- Ministry of Education Key Laboratory of Child Development and Disorders/National Clinical Research Center for Child Health and Disorders/China International Science and Technology Cooperation Base of Child Development and Critical Disorders/Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Li Jiang
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
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21
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GABAergic Transmission in the Basolateral Amygdala Differentially Modulates Plasticity in the Dentate Gyrus and the CA1 Areas. Int J Mol Sci 2020; 21:ijms21113786. [PMID: 32471158 PMCID: PMC7312428 DOI: 10.3390/ijms21113786] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/22/2020] [Accepted: 05/25/2020] [Indexed: 11/17/2022] Open
Abstract
The term "metaplasticity" is used to describe changes in synaptic plasticity sensitivity following an electrical, biochemical, or behavioral priming stimulus. For example, priming the basolateral amygdala (BLA) enhances long-term potentiation (LTP) in the dentate gyrus (DG) but decreases LTP in the CA1. However, the mechanisms underlying these metaplastic effects are only partly understood. Here, we examined whether the mechanism underlying these effects of BLA priming involves intra-BLA GABAergic neurotransmission. Low doses of muscimol, a GABAA receptor (GABAAR) agonist, were microinfused into the rat BLA before or after BLA priming. Our findings show that BLA GABAAR activation via muscimol mimicked the previously reported effects of electrical BLA priming on LTP in the perforant path and the ventral hippocampal commissure-CA1 pathways, decreasing CA1 LTP and increasing DG LTP. Furthermore, muscimol application before or after tetanic stimulation of the ventral hippocampal commissure-CA1 pathways attenuated the BLA priming-induced decrease in CA1 LTP. In contrast, muscimol application after tetanic stimulation of the perforant path attenuated the BLA priming-induced increase in DG LTP. The data indicate that GABAAR activation mediates metaplastic effects of the BLA on plasticity in the CA1 and the DG, but that the same GABAAR activation induces an intra-BLA form of metaplasticity, which alters the way BLA priming may modulate plasticity in other brain regions. These results emphasize the need for developing a dynamic model of BLA modulation of plasticity, a model that may better capture processes underlying memory alterations associated with emotional arousing or stressful events.
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22
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Sharifi KA, Rezayof A, Alijanpour S, Zarrindast MR. GABA-cannabinoid interplays in the dorsal hippocampus and basolateral amygdala mediate morphine-induced amnesia. Brain Res Bull 2020; 157:61-68. [DOI: 10.1016/j.brainresbull.2020.01.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 12/22/2022]
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23
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Promoting long-term inhibition of human fear responses by non-invasive transcutaneous vagus nerve stimulation during extinction training. Sci Rep 2020; 10:1529. [PMID: 32001763 PMCID: PMC6992620 DOI: 10.1038/s41598-020-58412-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 01/15/2020] [Indexed: 12/26/2022] Open
Abstract
Inhibiting fear-related thoughts and defensive behaviors when they are no longer appropriate to the situation is a prerequisite for flexible and adaptive responding to changing environments. Such inhibition of defensive systems is mediated by ventromedial prefrontal cortex (vmPFC), limbic basolateral amygdala (BLA), and brain stem locus-coeruleus noradrenergic system (LC-NAs). Non-invasive, transcutaneous vagus nerve stimulation (tVNS) has shown to activate this circuit. Using a multiple-day single-cue fear conditioning and extinction paradigm, we investigated long-term effects of tVNS on inhibition of low-level amygdala modulated fear potentiated startle and cognitive risk assessments. We found that administration of tVNS during extinction training facilitated inhibition of fear potentiated startle responses and cognitive risk assessments, resulting in facilitated formation, consolidation and long-term recall of extinction memory, and prevention of the return of fear. These findings might indicate new ways to increase the efficacy of exposure-based treatments of anxiety disorders.
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24
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A brainstem-central amygdala circuit underlies defensive responses to learned threats. Mol Psychiatry 2020; 25:640-654. [PMID: 31758092 PMCID: PMC7042728 DOI: 10.1038/s41380-019-0599-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 07/11/2019] [Accepted: 08/19/2019] [Indexed: 11/09/2022]
Abstract
Norepinephrine (NE) plays a central role in the acquisition of aversive learning via actions in the lateral nucleus of the amygdala (LA) [1, 2]. However, the function of NE in expression of aversively-conditioned responses has not been established. Given the role of the central nucleus of the amygdala (CeA) in the expression of such behaviors [3-5], and the presence of NE axons projections in this brain nucleus [6], we assessed the effects of NE activity in the CeA on behavioral expression using receptor-specific pharmacology and cell- and projection-specific chemogenetic manipulations. We found that inhibition and activation of locus coeruleus (LC) neurons decreases and increases freezing to aversively conditioned cues, respectively. We then show that locally inhibiting or activating LC terminals in CeA is sufficient to achieve this bidirectional modulation of defensive reactions. These findings support the hypothesis that LC projections to CeA are critical for the expression of defensive responses elicited by conditioned threats.
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25
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The capacity for acute exercise to modulate emotional memories: A review of findings and mechanisms. Neurosci Biobehav Rev 2019; 107:438-449. [DOI: 10.1016/j.neubiorev.2019.09.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 07/14/2019] [Accepted: 09/22/2019] [Indexed: 01/18/2023]
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26
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Haaker J, Maren S, Andreatta M, Merz CJ, Richter J, Richter SH, Meir Drexler S, Lange MD, Jüngling K, Nees F, Seidenbecher T, Fullana MA, Wotjak CT, Lonsdorf TB. Making translation work: Harmonizing cross-species methodology in the behavioural neuroscience of Pavlovian fear conditioning. Neurosci Biobehav Rev 2019; 107:329-345. [PMID: 31521698 DOI: 10.1016/j.neubiorev.2019.09.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 07/08/2019] [Accepted: 09/11/2019] [Indexed: 12/22/2022]
Abstract
Translational neuroscience bridges insights from specific mechanisms in rodents to complex functions in humans and is key to advance our general understanding of central nervous function. A prime example of translational research is the study of cross-species mechanisms that underlie responding to learned threats, by employing Pavlovian fear conditioning protocols in rodents and humans. Hitherto, evidence for (and critique of) these cross-species comparisons in fear conditioning research was based on theoretical viewpoints. Here, we provide a perspective to substantiate these theoretical concepts with empirical considerations of cross-species methodology. This meta-research perspective is expected to foster cross-species comparability and reproducibility to ultimately facilitate successful transfer of results from basic science into clinical applications.
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Affiliation(s)
- Jan Haaker
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Stephen Maren
- Department of Psychological and Brain Sciences and Institute for Neuroscience, Texas A&M University, College Station, TX, 77843, USA
| | - Marta Andreatta
- Department of Psychology, University of Würzburg, Würzburg, Germany; Department of Psychology, Education & Child Studies, Erasmus University Rotterdam, Netherlands
| | - Christian J Merz
- Ruhr University Bochum, Faculty of Psychology, Institute of Cognitive Neuroscience, Department of Cognitive Psychology, Germany
| | - Jan Richter
- Department of Biological and Clinical Psychology/Psychotherapy, University of Greifswald, Greifswald, Germany
| | - S Helene Richter
- Department of Behavioural Biology, University of Münster, Münster, Germany
| | - Shira Meir Drexler
- Ruhr University Bochum, Faculty of Psychology, Institute of Cognitive Neuroscience, Department of Cognitive Psychology, Germany
| | - Maren D Lange
- Institute of Physiology I, University of Münster, Münster, Germany
| | - Kay Jüngling
- Institute of Physiology I, University of Münster, Münster, Germany
| | - Frauke Nees
- Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | | | - Miquel A Fullana
- Institute of Neurosciences, Hospital Clinic, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain
| | - Carsten T Wotjak
- Neuronal Plasticity Research Group, Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - Tina B Lonsdorf
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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27
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Souza RR, Robertson NM, Pruitt DT, Gonzales PA, Hays SA, Rennaker RL, Kilgard MP, McIntyre CK. Vagus nerve stimulation reverses the extinction impairments in a model of PTSD with prolonged and repeated trauma. Stress 2019; 22:509-520. [PMID: 31010369 DOI: 10.1080/10253890.2019.1602604] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We have shown that vagus nerve stimulation (VNS) enhances extinction of conditioned fear and reduces anxiety in rat models of PTSD using moderate stress. However, it is still unclear if VNS can be effective in enhancing extinction of severe fear after prolonged and repeated trauma. Severe fear was induced in adult male rats by combining single prolonged stress (SPS) and protracted aversive conditioning (PAC). After SPS and PAC procedures, rats were implanted with stimulating cuff electrodes, exposed to five days of extinction training with or without VNS, and then tested for extinction retention, return of fear in a new context and reinstatement. The elevated plus maze, open field and startle were used to test anxiety. Sham rats showed no reduction of fear during extensive extinction training. VNS-paired with extinction training reduced freezing at the last extinction session by 70% compared to sham rats. VNS rats exhibited half as much fear as shams, as well as less fear renewal. Sham rats exhibited significantly more anxiety than naive controls, whereas VNS rats did not. These results demonstrate that VNS enhances extinction and reduces anxiety in a severe model of PTSD that combined SPS and a conditioning procedure that is 30 times more intense than the conditioning procedures in previous VNS studies. The broad utility of VNS in enhancing extinction learning in rats and the strong clinical safety record of VNS suggest that VNS holds promise as an adjuvant to exposure-based therapy in people with PTSD and other complex forms of this condition.
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Affiliation(s)
- Rimenez R Souza
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
- b School of Behavioral Brain Sciences , The University of Texas at Dallas , Richardson , TX , USA
| | - Nicole M Robertson
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
| | - David T Pruitt
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
- b School of Behavioral Brain Sciences , The University of Texas at Dallas , Richardson , TX , USA
- c Erik Jonsson School of Engineering and Computer Science , The University of Texas at Dallas , Richardson , TX , USA
| | - Phillip A Gonzales
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
| | - Seth A Hays
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
- c Erik Jonsson School of Engineering and Computer Science , The University of Texas at Dallas , Richardson , TX , USA
| | - Robert L Rennaker
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
- b School of Behavioral Brain Sciences , The University of Texas at Dallas , Richardson , TX , USA
- c Erik Jonsson School of Engineering and Computer Science , The University of Texas at Dallas , Richardson , TX , USA
| | - Michael P Kilgard
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
- b School of Behavioral Brain Sciences , The University of Texas at Dallas , Richardson , TX , USA
| | - Christa K McIntyre
- a Texas Biomedical Device Center , The University of Texas at Dallas , Richardson , TX , USA
- b School of Behavioral Brain Sciences , The University of Texas at Dallas , Richardson , TX , USA
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28
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Velasco ER, Florido A, Milad MR, Andero R. Sex differences in fear extinction. Neurosci Biobehav Rev 2019; 103:81-108. [PMID: 31129235 DOI: 10.1016/j.neubiorev.2019.05.020] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 03/08/2019] [Accepted: 05/19/2019] [Indexed: 12/18/2022]
Abstract
Despite the exponential increase in fear research during the last years, few studies have included female subjects in their design. The need to include females arises from the knowledge gap of mechanistic processes underlying the behavioral and neural differences observed in fear extinction. Moreover, the exact contribution of sex and hormones in relation to learning and behavior is still largely unknown. Insights from this field could be beneficial as fear-related disorders are twice as prevalent in women compared to men. Here, we review an up-to-date summary of animal and human studies in adulthood that report sex differences in fear extinction from a structural and functional approach. Furthermore, we describe how these factors could contribute to the observed sex differences in fear extinction during normal and pathological conditions.
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Affiliation(s)
- E R Velasco
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain
| | - A Florido
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain
| | - M R Milad
- Department of Psychiatry, University of Illinois at Chicago, USA
| | - R Andero
- Institut de Neurociències, Universitat Autònoma de Barcelona, Spain; CIBERSAM, Corporació Sanitaria Parc Taulí, Sabadell, Spain; Department of Psychobiology and Methodology of Health Sciences, Universitat Autònoma de Barcelona, Spain.
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Lebois LAM, Seligowski AV, Wolff JD, Hill SB, Ressler KJ. Augmentation of Extinction and Inhibitory Learning in Anxiety and Trauma-Related Disorders. Annu Rev Clin Psychol 2019; 15:257-284. [PMID: 30698994 DOI: 10.1146/annurev-clinpsy-050718-095634] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Although the fear response is an adaptive response to threatening situations, a number of psychiatric disorders feature prominent fear-related symptoms caused, in part, by failures of extinction and inhibitory learning. The translational nature of fear conditioning paradigms has enabled us to develop a nuanced understanding of extinction and inhibitory learning based on the molecular substrates to systems neural circuitry and psychological mechanisms. This knowledge has facilitated the development of novel interventions that may augment extinction and inhibitory learning. These interventions include nonpharmacological techniques, such as behavioral methods to implement during psychotherapy, as well as device-based stimulation techniques that enhance or reduce activity in different regions of the brain. There is also emerging support for a number of psychopharmacological interventions that may augment extinction and inhibitory learning specifically if administered in conjunction with exposure-based psychotherapy. This growing body of research may offer promising novel techniques to address debilitating transdiagnostic fear-related symptoms.
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Affiliation(s)
- Lauren A M Lebois
- Division of Depression and Anxiety Disorders, Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, Massachusetts 02478, USA;
| | - Antonia V Seligowski
- Division of Depression and Anxiety Disorders, Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, Massachusetts 02478, USA;
| | - Jonathan D Wolff
- Division of Depression and Anxiety Disorders, Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, Massachusetts 02478, USA;
| | - Sarah B Hill
- Division of Depression and Anxiety Disorders, Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, Massachusetts 02478, USA;
| | - Kerry J Ressler
- Division of Depression and Anxiety Disorders, Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, Massachusetts 02478, USA;
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Noble LJ, Souza RR, McIntyre CK. Vagus nerve stimulation as a tool for enhancing extinction in exposure-based therapies. Psychopharmacology (Berl) 2019; 236:355-367. [PMID: 30091004 PMCID: PMC6368475 DOI: 10.1007/s00213-018-4994-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 08/01/2018] [Indexed: 02/04/2023]
Abstract
RATIONALE Emotionally traumatic experiences can lead to maladaptive memories that are enduring and intrusive. The goal of exposure-based therapies is to extinguish conditioned fears through repeated, unreinforced exposures to reminders of traumatic events. The extinction of conditioned fear depends upon the consolidation of new memories made during exposure to reminders. An impairment in extinction recall, observed in certain patient populations, can interfere with progress in exposure-based therapies, and the drive to avoid thoughts and reminders of the trauma can undermine compliance and increase dropout rate. Effective adjuncts to exposure-based therapies should improve the consolidation and maintenance of the extinction memory or improve the tolerability of the therapy. Under stressful conditions, the vagus nerve responds to elevations in epinephrine and signals the brain to facilitate the storage of new memories while, as part of the parasympathetic nervous system, it slows the sympathetic response. OBJECTIVE Here, we review studies relevant to fear extinction, describing the anatomical and functional characteristics of the vagus nerve and mechanisms of vagus nerve stimulation (VNS)-induced memory enhancement and plasticity. RESULTS We propose that stimulation of the left cervical vagus nerve during exposure to conditioned cues signals the brain to store new memories just as epinephrine or emotional arousal would do, but bypasses the peripheral sympathetic "fight-or-flight" response. CONCLUSIONS In support of this hypothesis, we have found that VNS accelerates extinction and prevents reinstatement of conditioned fear in rats. Finally, we propose future studies targeting the optimization of stimulation parameters and the search for biomarkers of VNS effectiveness that may improve exposure therapy outcomes.
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Shi L, Chen SJ, Deng JH, Que JY, Lin X, Sun Y, Bao YP, Shi J, Lu L. ADRB2 gene polymorphism modulates the retention of fear extinction memory. Neurobiol Learn Mem 2018; 156:96-102. [PMID: 30423370 DOI: 10.1016/j.nlm.2018.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 10/12/2018] [Accepted: 11/09/2018] [Indexed: 12/20/2022]
Abstract
Individual differences in regulation of fear and extinction memory play significant roles in the aetiology development of post-traumatic stress disorder (PTSD). Previous animal based studies showed that the activity of β-adrenergic receptors (β-ARs) are involved in memory modulation. However in humans it is not clear that whether genetic variability in β-ARs contributes to individual differences of fear and extinction memory. In the current study, we investigated the role of a common single-nucleotide polymorphism of β2-adrenergic receptor (ADRB2) gene in fear memory acquisition, fear memory extinction, extinction recall and fear generalization in human participants. Ninety-one male participants were exposed to a Pavlovian fear conditioning and their fear responses were assessed by the skin conductance response. Participants were genotyped for a polymorphism (rs2400207) located within the promoter region of the human ADRB2. Differences between genotypes were observed in the extinction memory recall test but not in fear acquisition, extinction learning and fear generalization. Particularly, A-allele carriers of rs2400707 displayed successful retention of extinction memory and prevented the return of fear during recall test. The results revealed the involvement of human noradrenergic system in the retention of extinction memory and genetic variability in this system may underlie individual differences in PTSD. Furthermore, rs2400207 polymorphism of ADRB2 gene may play a key role in the treatment efficacy of PTSD and can be a basis for future studies investigating a personalized medicine for fear memory related disorders.
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Affiliation(s)
- Le Shi
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China
| | - Si-Jing Chen
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China; Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong Special Administrative Region
| | - Jia-Hui Deng
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China
| | - Jian-Yu Que
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China
| | - Xiao Lin
- Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Yan Sun
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Yan-Ping Bao
- National Institute on Drug Dependence, Peking University, Beijing, China
| | - Jie Shi
- National Institute on Drug Dependence, Peking University, Beijing, China.
| | - Lin Lu
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Beijing, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, China.
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Modulation of the endocannabinoid system by sex hormones: Implications for posttraumatic stress disorder. Neurosci Biobehav Rev 2018; 94:302-320. [DOI: 10.1016/j.neubiorev.2018.07.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 07/10/2018] [Accepted: 07/10/2018] [Indexed: 12/11/2022]
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Vagus nerve stimulation promotes generalization of conditioned fear extinction and reduces anxiety in rats. Brain Stimul 2018; 12:9-18. [PMID: 30287193 DOI: 10.1016/j.brs.2018.09.013] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 09/17/2018] [Accepted: 09/19/2018] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Exposure-based therapies are used to treat a variety of trauma- and anxiety-related disorders by generating successful extinction following cue exposure during treatment. The development of adjuvant strategies that accelerate extinction learning, improve tolerability, and increase efficiency of treatment could increase the efficacy of exposure-based therapies. Vagus nerve stimulation (VNS) paired with exposure can enhance fear extinction, in rat models of psychiatric disorders, and chronic administration of VNS reduces anxiety in rats and humans. OBJECTIVE We tested whether VNS, like other cognitive enhancers, could produce generalization of extinction for stimuli that are not presented during the extinction sessions, but are associated with the fear event. METHODS Male Sprague Dawley rats underwent auditory fear conditioning with two easily discriminable auditory stimuli. Following fear conditioning, extinction training consisted of exposure to only one of the conditioned sounds. Half of the rats received VNS and half received sham stimulation during with sound presentations. VNS effects on anxiety were examined in a separate study where VNS was administered prior to testing on the elevated plus maze. RESULTS Sham stimulated rats given 20 presentations of a conditioned stimulus (CS) during the extinction session showed performance that was matched to VNS-treated rats given only 4 presentations of the CS. Despite comparable levels of freezing to the presented CS, only the VNS-treated rats showed a significant decrease in freezing to the CS that was not presented. VNS-induced generalization of extinction was observed only when the two sounds were paired with footshock within the same fear conditioning session; VNS did not promote generalization of extinction when the two sounds were conditioned on different days or in different contexts. On the anxiety test, VNS administration significantly increased time spent in the open arms of the elevated plus maze. CONCLUSION These results provide evidence that VNS can promote generalization of extinction to other stimuli associated with a specific fear experience. Furthermore, non-contingent VNS appears to reduce anxiety. The ability to generalize extinction and reduce anxiety makes VNS a potential candidate for use as an adjunctive strategy to improve the efficacy and tolerability of exposure-based therapies.
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MDMA-assisted psychotherapy for PTSD: Are memory reconsolidation and fear extinction underlying mechanisms? Prog Neuropsychopharmacol Biol Psychiatry 2018. [PMID: 29524515 DOI: 10.1016/j.pnpbp.2018.03.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
MDMA-assisted psychotherapy for treatment of PTSD has recently progressed to Phase 3 clinical trials and received Breakthrough Therapy designation by the FDA. MDMA used as an adjunct during psychotherapy sessions has demonstrated effectiveness and acceptable safety in reducing PTSD symptoms in Phase 2 trials, with durable remission of PTSD diagnosis in 68% of participants. The underlying psychological and neurological mechanisms for the robust effects in mitigating PTSD are being investigated in animal models and in studies of healthy volunteers. This review explores the potential role of memory reconsolidation and fear extinction during MDMA-assisted psychotherapy. MDMA enhances release of monoamines (serotonin, norepinephrine, dopamine), hormones (oxytocin, cortisol), and other downstream signaling molecules (BDNF) to dynamically modulate emotional memory circuits. By reducing activation in brain regions implicated in the expression of fear- and anxiety-related behaviors, namely the amygdala and insula, and increasing connectivity between the amygdala and hippocampus, MDMA may allow for reprocessing of traumatic memories and emotional engagement with therapeutic processes. Based on the pharmacology of MDMA and the available translational literature of memory reconsolidation, fear learning, and PTSD, this review suggests a neurobiological rationale to explain, at least in part, the large effect sizes demonstrated for MDMA in treating PTSD.
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Fidelman S, Mizrachi Zer-Aviv T, Lange R, Hillard CJ, Akirav I. Chronic treatment with URB597 ameliorates post-stress symptoms in a rat model of PTSD. Eur Neuropsychopharmacol 2018. [PMID: 29519609 DOI: 10.1016/j.euroneuro.2018.02.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Activating the endocannabinoid system has become a major focus in the search for novel therapeutics for anxiety and deficits in fear extinction, two defining features of PTSD. We examined whether chronic treatment with the fatty acid amide hydrolase (FAAH) inhibitor URB597 (0.2, 0.3, 0.4 mg/kg, i.p.) or the CB1/2 receptor agonist WIN55,212-2 (0.25, 0.5 mg/kg, i.p.) injected for 3 weeks to rats exposed to the shock and reminders model of PTSD would attenuate post-stress symptoms and affect basolateral amygdala (BLA) and CA1 CB1 receptors. Exposure to shock and reminders enhanced acoustic startle response and impaired extinction. Rats exposed to shock and reminders and chronically treated with URB597 demonstrated normalized startle response and intact extinction kinetics. WIN55,212-2 only affected the startle response. The therapeutic effects of URB597 and WIN55,212-2 were found to be CB1 receptor dependent, as these effects were blocked when a low dose of the CB1 receptor antagonist AM251 (0.3 mg/kg, i.p. for 3 weeks) was co-administered. Moreover, URB597, but not WIN55,212-2, normalized the shock/reminders-induced upregulation in CB1 receptor levels in the BLA and CA1. One hour after the shock, N-arachidonoylethanolamine (AEA) was increased in the BLA and decreased in the CA1. Circulating 2-arachidonoylglycerol (2-AG) concentrations were decreased in shocked rats, with no significant effect in the BLA or CA1. FAAH activity was increased in the CA1 of shocked rats. Chronic cannabinoid treatment with URB597 can ameliorate PTSD-like symptoms suggesting FAAH inhibitors as a potentially effective therapeutic strategy for the treatment of disorders associated with inefficient fear coping.
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MESH Headings
- Amidohydrolases/antagonists & inhibitors
- Amidohydrolases/metabolism
- Animals
- Arachidonic Acids/blood
- Basolateral Nuclear Complex/metabolism
- Benzamides/administration & dosage
- Benzamides/pharmacology
- Benzoxazines/administration & dosage
- Benzoxazines/pharmacology
- CA1 Region, Hippocampal/metabolism
- Cannabinoid Receptor Antagonists/pharmacology
- Carbamates/administration & dosage
- Carbamates/pharmacology
- Dose-Response Relationship, Drug
- Electric Stimulation
- Endocannabinoids/blood
- Endocannabinoids/metabolism
- Extinction, Psychological/drug effects
- Glycerides/blood
- Male
- Morpholines/administration & dosage
- Morpholines/pharmacology
- Naphthalenes/administration & dosage
- Naphthalenes/pharmacology
- Piperidines/pharmacology
- Polyunsaturated Alkamides
- Pyrazoles/pharmacology
- Rats
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/physiology
- Reflex, Startle/drug effects
- Reflex, Startle/physiology
- Stress Disorders, Post-Traumatic/drug therapy
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Affiliation(s)
- Sharon Fidelman
- Department of Psychology, University of Haifa, Haifa 3498838, Israel
| | | | - Rachel Lange
- Department of Pharmacology and Toxicology, Neuroscience Research Center, Medical College of Wisconsin, Milwaukee 53226, USA
| | - Cecilia J Hillard
- Department of Pharmacology and Toxicology, Neuroscience Research Center, Medical College of Wisconsin, Milwaukee 53226, USA
| | - Irit Akirav
- Department of Psychology, University of Haifa, Haifa 3498838, Israel.
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Chesworth R, Corbit LH. Noradrenergic β-receptor antagonism in the basolateral amygdala impairs reconsolidation, but not extinction, of alcohol self-administration: Intra-BLA propranolol impairs reconsolidation of alcohol self-administration. Neurobiol Learn Mem 2018; 151:59-70. [PMID: 29649583 DOI: 10.1016/j.nlm.2018.04.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/19/2018] [Accepted: 04/06/2018] [Indexed: 11/26/2022]
Abstract
A critical barrier to recovery from alcohol addiction is relapse propensity. Alcohol cues can trigger relapse, and pharmacologically facilitating processes such as extinction, which decreases cue associations, may help prevent relapse. The noradrenergic system mediates extinction learning for alcohol; however, the neural locus of this effect is unknown. This study sought to determine whether the basolateral amygdala (BLA), a region critical for fear extinction, also mediates extinction of alcohol seeking. Hooded Wistar rats (N = 12-15 per experiment) were implanted with bilateral cannula targeting the BLA and trained to lever press for 10% ethanol during auditory or visual cues. Infusions of the β-receptor antagonist propranolol (2 µg/side) were administered prior to extinction (Experiment 1), and rats assessed for relapse-like behaviour two weeks later, thus allowing for spontaneous recovery. We expected intra-BLA propranolol to impair extinction learning; however, propranolol-treated rats exhibited reduced responding in the test of spontaneous recovery, suggesting enhanced extinction. We investigated this unexpected result by determining if propranolol treatment affected memory processes other than extinction. In a subsequent experiment, rats were infused with propranolol immediately after extinction to target consolidation of extinction (Experiment 2a), and assessed for spontaneous recovery. Propranolol was also infused after self-administration to target reconsolidation of the original learning (Experiment 2b). Propranolol treatment had no effect on consolidation of extinction learning, but impaired reconsolidation of self-administration. Propranolol administered prior to a self-administration session did not affect reinforced responding (Experiment 2c). Extinction and reconsolidation are opposing processes triggered by specific test conditions. We suggest our test conditions induced reconsolidation of self-administration memory by propranolol, rather than modulation of extinction. Thus, our data implicates intra-BLA noradrenergic β-receptors in reconsolidation of alcohol self-administration memory.
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Giustino TF, Maren S. Noradrenergic Modulation of Fear Conditioning and Extinction. Front Behav Neurosci 2018; 12:43. [PMID: 29593511 PMCID: PMC5859179 DOI: 10.3389/fnbeh.2018.00043] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 02/26/2018] [Indexed: 12/12/2022] Open
Abstract
The locus coeruleus norepinephrine (LC-NE) system plays a broad role in learning and memory. Here we begin with an overview of the LC-NE system. We then consider how both direct and indirect manipulations of the LC-NE system affect cued and contextual aversive learning and memory. We propose that NE dynamically modulates Pavlovian conditioning and extinction, either promoting or impairing learning aversive processes under different levels of behavioral arousal. We suggest that under high levels of stress (e.g., during/soon after fear conditioning) the locus coeruleus (LC) promotes cued fear learning by enhancing amygdala function while simultaneously blunting prefrontal function. Under low levels of arousal, the LC promotes PFC function to promote downstream inhibition of the amygdala and foster the extinction of cued fear. Thus, LC-NE action on the medial prefrontal cortex (mPFC) might be described by an inverted-U function such that it can either enhance or hinder learning depending on arousal states. In addition, LC-NE seems to be particularly important for the acquisition, consolidation and extinction of contextual fear memories. This may be due to dense adrenoceptor expression in the hippocampus (HPC) which encodes contextual information, and the ability of NE to regulate long-term potentiation (LTP). Moreover, recent work reveals that the diversity of LC-NE functions in aversive learning and memory are mediated by functionally heterogeneous populations of LC neurons that are defined by their projection targets. Hence, LC-NE function in learning and memory is determined by projection-specific neuromodulation that accompanies various states of behavioral arousal.
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Affiliation(s)
- Thomas F Giustino
- Department of Psychological and Brain Sciences, Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, United States
| | - Stephen Maren
- Department of Psychological and Brain Sciences, Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, United States
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Breit S, Kupferberg A, Rogler G, Hasler G. Vagus Nerve as Modulator of the Brain-Gut Axis in Psychiatric and Inflammatory Disorders. Front Psychiatry 2018; 9:44. [PMID: 29593576 PMCID: PMC5859128 DOI: 10.3389/fpsyt.2018.00044] [Citation(s) in RCA: 462] [Impact Index Per Article: 77.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 02/01/2018] [Indexed: 12/13/2022] Open
Abstract
The vagus nerve represents the main component of the parasympathetic nervous system, which oversees a vast array of crucial bodily functions, including control of mood, immune response, digestion, and heart rate. It establishes one of the connections between the brain and the gastrointestinal tract and sends information about the state of the inner organs to the brain via afferent fibers. In this review article, we discuss various functions of the vagus nerve which make it an attractive target in treating psychiatric and gastrointestinal disorders. There is preliminary evidence that vagus nerve stimulation is a promising add-on treatment for treatment-refractory depression, posttraumatic stress disorder, and inflammatory bowel disease. Treatments that target the vagus nerve increase the vagal tone and inhibit cytokine production. Both are important mechanism of resiliency. The stimulation of vagal afferent fibers in the gut influences monoaminergic brain systems in the brain stem that play crucial roles in major psychiatric conditions, such as mood and anxiety disorders. In line, there is preliminary evidence for gut bacteria to have beneficial effect on mood and anxiety, partly by affecting the activity of the vagus nerve. Since, the vagal tone is correlated with capacity to regulate stress responses and can be influenced by breathing, its increase through meditation and yoga likely contribute to resilience and the mitigation of mood and anxiety symptoms.
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Affiliation(s)
- Sigrid Breit
- Division of Molecular Psychiatry, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Aleksandra Kupferberg
- Division of Molecular Psychiatry, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Gerhard Rogler
- Department of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland
| | - Gregor Hasler
- Division of Molecular Psychiatry, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
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Does exercise augment operant and Pavlovian extinction: A meta-analysis. J Psychiatr Res 2018; 96:73-93. [PMID: 28987515 DOI: 10.1016/j.jpsychires.2017.09.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/17/2017] [Accepted: 09/14/2017] [Indexed: 12/16/2022]
Abstract
BACKGROUND Exposure therapy, a behavioral approach to reduce symptomology in fear, anxiety, and drug-related psychiatric disorders, is based on learning and memory principles of extinction, and is subject to relapse. As such, it is important to find ways to enhance outcomes. One such way is through exercise. OBJECTIVES Identify if exercise augments extinction behavior, and whether this depends on the experimental paradigm used (i.e. operant or Pavlovian) and/or stimulus (i.e. appetitive or aversive). Additionally, determine which moderating variables influence the effects of exercise on extinction learning. METHODS A literature search was conducted and a Hedges' g calculation was employed to conduct a meta-analysis (metaSEM) using a structural equation modeling approach. This approach was chosen because of its ability to account for dependencies in effect sizes. RESULTS We found a significant effect of exercise as an augmentation over extinction alone (g = 0.37, p < 0.001), with extinction paradigm (but not stimulus) producing a moderating effect (B = 0.43, p = 0.030). Data were then split by extinction paradigm, with operant extinction models having a significant effect (g = 0.55, p < 0.001), and number of extinction sessions moderating aggregate effects. Pavlovian models did not have significant overall effects (g = 0.11, p = 0.3976), but were moderated by the number of animals housed together and exercise after extinction. CONCLUSIONS The effects of exercise on extinction learning are differentially modulated by the type of paradigm used, the number of extinction sessions, the timing of when exercise treatment was applied (after extinction), and the housing conditions.
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Cao B, Ni HY, Li J, Zhou Y, Bian XL, Tao Y, Cai CY, Qin C, Wu HY, Chang L, Luo CX, Zhu DY. (+)-Borneol suppresses conditioned fear recall and anxiety-like behaviors in mice. Biochem Biophys Res Commun 2017; 495:1588-1593. [PMID: 29223397 DOI: 10.1016/j.bbrc.2017.12.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Accepted: 12/05/2017] [Indexed: 01/19/2023]
Abstract
Fear- and anxiety-related psychiatric disorders have been one of the major chronic diseases afflicting patients for decades, and new compounds for treating such disorders remain to be developed. (+)-Borneol, a bicyclic monoterpene found in several species of Artemisia and Dipterocarpaceae, is widely used for anxiety, pain and anesthesia in Chinese medicine. Meanwhile, it can potentiate GABA (γ-aminobutyric acid) activity directly in recombinant GABAA receptors. The present study was to investigate the effects of (+)-Borneol on both contextual and cued fear recall. Interestingly, microinjection of (+)-Borneol into the dorsal hippocampus inhibited 24 h and 7 d contextual fear, whereas its infusion into ventral hippocampus only reduced 24 h cued fear responses. Moreover, microinjection of (+)-Borneol into dorsal but not ventral hippocampus suppressed anxiety-like behaviors in the open field test, light/dark exploration and the elevated plus maze test. As selective GABAA receptor antagonist bicuculline reversed the effect of (+)-Borneol on contextual fear paradigm and the drug potentiated GABA-evoked currents in acute hippocampus slices, modulation of the GABAergic neurotransmission may explain the effects of (+)-Borneol. Our findings suggest that (+)-Borneol can serve as a new therapeutic in fear- and anxiety-related disorders.
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Affiliation(s)
- Bo Cao
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Huan-Yu Ni
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Jun Li
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Ying Zhou
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Xin-Lan Bian
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Yan Tao
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Cheng-Yun Cai
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Cheng Qin
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Hai-Yin Wu
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Lei Chang
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Chun-Xia Luo
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Dong-Ya Zhu
- Department of Pharmacology, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China; Key Laboratory of Precision Medicine of Cardiovascular Disease, Nanjing Medical University, Nanjing 211166, China; Institution of Stem Cells and Neuroregeneration, Nanjing Medical University, Nanjing 211166, China.
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Huang B, Zhu H, Zhou Y, Liu X, Ma L. Unconditioned- and Conditioned- Stimuli Induce Differential Memory Reconsolidation and β-AR-Dependent CREB Activation. Front Neural Circuits 2017; 11:53. [PMID: 28848401 PMCID: PMC5554378 DOI: 10.3389/fncir.2017.00053] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 07/21/2017] [Indexed: 11/13/2022] Open
Abstract
Consolidated long-term fear memories become labile and reconsolidated upon retrieval by the presentation of conditioned stimulus (CS) or unconditioned stimulus (US). Whether CS-retrieval or US-retrieval will trigger different memory reconsolidation processes is unknown. In this study, we introduced a sequential fear conditioning paradigm in which footshock (FS) was paired with two distinct sounds (CS-A and CS-B). The treatment with propranolol, a β-adrenergic receptor (β-AR) antagonist, after US (FS)-retrieval impaired freezing behavior evoked by either CS-A or CS-B. Betaxolol, a selective β1-AR antagonist, showed similar effects. However, propranolol treatment after retrieval by one CS (e.g., CS-A) only inhibited freezing behavior evoked by the same CS (i.e., CS-A), not the other CS (CS-B). These data suggest that β-AR is critically involved in reconsolidation of fear memory triggered by US- and CS-retrieval, whereas β-AR blockade after US-retrieval disrupts more CS-US associations than CS-retrieval does. Furthermore, significant CREB activation in almost the whole amygdala and hippocampus was observed after US-retrieval, but CS-retrieval only stimulated CREB activation in the lateral amygdala and the CA3 of hippocampus. In addition, propranolol treatment suppressed memory retrieval-induced CREB activation. These data indicate that US-retrieval activates more memory traces than CS-retrieval does, leading to memory reconsolidation of more CS-US associations.
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Affiliation(s)
- Bing Huang
- The State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences and the Institutes of Brain Science, and Department of Translational Neuroscience, Shanghai Pudong Hospital, Fudan UniversityShanghai, China
| | - Huiwen Zhu
- The State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences and the Institutes of Brain Science, and Department of Translational Neuroscience, Shanghai Pudong Hospital, Fudan UniversityShanghai, China
| | - Yiming Zhou
- The State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences and the Institutes of Brain Science, and Department of Translational Neuroscience, Shanghai Pudong Hospital, Fudan UniversityShanghai, China
| | - Xing Liu
- The State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences and the Institutes of Brain Science, and Department of Translational Neuroscience, Shanghai Pudong Hospital, Fudan UniversityShanghai, China
| | - Lan Ma
- The State Key Laboratory of Medical Neurobiology, School of Basic Medical Sciences and the Institutes of Brain Science, and Department of Translational Neuroscience, Shanghai Pudong Hospital, Fudan UniversityShanghai, China
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The Small GTPase Rac1 Contributes to Extinction of Aversive Memories of Drug Withdrawal by Facilitating GABA A Receptor Endocytosis in the vmPFC. J Neurosci 2017. [PMID: 28630256 DOI: 10.1523/jneurosci.3859-16.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Extinction of aversive memories has been a major concern in neuropsychiatric disorders, such as anxiety disorders and drug addiction. However, the mechanisms underlying extinction of aversive memories are not fully understood. Here, we report that extinction of conditioned place aversion (CPA) to naloxone-precipitated opiate withdrawal in male rats activates Rho GTPase Rac1 in the ventromedial prefrontal cortex (vmPFC) in a BDNF-dependent manner, which determines GABAA receptor (GABAAR) endocytosis via triggering synaptic translocation of activity-regulated cytoskeleton-associated protein (Arc) through facilitating actin polymerization. Active Rac1 is essential and sufficient for GABAAR endocytosis and CPA extinction. Knockdown of Rac1 expression within the vmPFC of rats using Rac1-shRNA suppressed GABAAR endocytosis and CPA extinction, whereas expression of a constitutively active form of Rac1 accelerated GABAAR endocytosis and CPA extinction. The crucial role of GABAAR endocytosis in the LTP induction and CPA extinction is evinced by the findings that blockade of GABAAR endocytosis by a dynamin function-blocking peptide (Myr-P4) abolishes LTP induction and CPA extinction. Thus, the present study provides first evidence that Rac1-dependent GABAAR endocytosis plays a crucial role in extinction of aversive memories and reveals the sequence of molecular events that contribute to learning experience modulation of synaptic GABAAR endocytosis.SIGNIFICANCE STATEMENT This study reveals that Rac1-dependent GABAAR endocytosis plays a crucial role in extinction of aversive memories associated with drug withdrawal and identifies Arc as a downstream effector of Rac1 regulations of synaptic plasticity as well as learning and memory, thereby suggesting therapeutic targets to promote extinction of the unwanted memories.
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One-single physical exercise session after object recognition learning promotes memory persistence through hippocampal noradrenergic mechanisms. Behav Brain Res 2017; 329:120-126. [DOI: 10.1016/j.bbr.2017.04.050] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 04/23/2017] [Accepted: 04/26/2017] [Indexed: 12/18/2022]
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LaLumiere RT, McGaugh JL, McIntyre CK. Emotional Modulation of Learning and Memory: Pharmacological Implications. Pharmacol Rev 2017; 69:236-255. [PMID: 28420719 DOI: 10.1124/pr.116.013474] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/03/2017] [Indexed: 01/06/2023] Open
Abstract
Memory consolidation involves the process by which newly acquired information becomes stored in a long-lasting fashion. Evidence acquired over the past several decades, especially from studies using post-training drug administration, indicates that emotional arousal during the consolidation period influences and enhances the strength of the memory and that multiple different chemical signaling systems participate in this process. The mechanisms underlying the emotional influences on memory involve the release of stress hormones and activation of the basolateral amygdala, which work together to modulate memory consolidation. Moreover, work suggests that this amygdala-based memory modulation occurs with numerous types of learning and involves interactions with many different brain regions to alter consolidation. Additionally, studies suggest that emotional arousal and amygdala activity in particular influence synaptic plasticity and associated proteins in downstream brain regions. This review considers the historical understanding for memory modulation and cellular consolidation processes and examines several research areas currently using this foundational knowledge to develop therapeutic treatments.
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Affiliation(s)
- Ryan T LaLumiere
- Department of Psychological and Brain Sciences and Interdisciplinary Neuroscience Program, University of Iowa, Iowa City, Iowa (R.T.L.); Department of Neurobiology and Behavior, University of California, Irvine, California (J.L.M.); and School of Behavioral and Brain Sciences, University of Texas-Dallas, Richardson, Texas (C.K.M.)
| | - James L McGaugh
- Department of Psychological and Brain Sciences and Interdisciplinary Neuroscience Program, University of Iowa, Iowa City, Iowa (R.T.L.); Department of Neurobiology and Behavior, University of California, Irvine, California (J.L.M.); and School of Behavioral and Brain Sciences, University of Texas-Dallas, Richardson, Texas (C.K.M.)
| | - Christa K McIntyre
- Department of Psychological and Brain Sciences and Interdisciplinary Neuroscience Program, University of Iowa, Iowa City, Iowa (R.T.L.); Department of Neurobiology and Behavior, University of California, Irvine, California (J.L.M.); and School of Behavioral and Brain Sciences, University of Texas-Dallas, Richardson, Texas (C.K.M.)
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45
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Future Targets for Female Sexual Dysfunction. J Sex Med 2016; 13:1147-65. [DOI: 10.1016/j.jsxm.2016.05.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 05/22/2016] [Accepted: 05/27/2016] [Indexed: 12/18/2022]
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46
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Zuj DV, Palmer MA, Lommen MJJ, Felmingham KL. The centrality of fear extinction in linking risk factors to PTSD: A narrative review. Neurosci Biobehav Rev 2016; 69:15-35. [PMID: 27461912 DOI: 10.1016/j.neubiorev.2016.07.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 02/08/2023]
Abstract
Recent prospective studies in emergency services have identified impaired fear extinction learning and memory to be a significant predictor of Posttraumatic Stress Disorder (PTSD), complementing a wealth of cross-sectional evidence of extinction deficits associated with the disorder. Additional fields of research show specific risk factors and biomarkers of the disorder, including candidate genotypes, stress and sex hormones, cognitive factors, and sleep disturbances. Studies in mostly nonclinical populations also reveal that the aforementioned factors are involved in fear extinction learning and memory. Here, we provide a comprehensive narrative review of the literature linking PTSD to these risk factors, and linking these risk factors to impaired fear extinction. On balance, the evidence suggests that fear extinction may play a role in the relationship between risk factors and PTSD. Should this notion hold true, this review carries important implications for the improvement of exposure-based treatments, as well as strategies for the implementation of treatment.
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Affiliation(s)
- Daniel V Zuj
- Division of Psychology, School of Medicine, University of Tasmania, Tasmania, Australia.
| | - Matthew A Palmer
- Division of Psychology, School of Medicine, University of Tasmania, Tasmania, Australia
| | - Miriam J J Lommen
- Department of Psychology, University of Groningen, Groningen, The Netherlands
| | - Kim L Felmingham
- Division of Psychology, School of Medicine, University of Tasmania, Tasmania, Australia
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Burger AM, Verkuil B, Van Diest I, Van der Does W, Thayer JF, Brosschot JF. The effects of transcutaneous vagus nerve stimulation on conditioned fear extinction in humans. Neurobiol Learn Mem 2016; 132:49-56. [DOI: 10.1016/j.nlm.2016.05.007] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/13/2016] [Accepted: 05/20/2016] [Indexed: 12/30/2022]
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Knox D. The role of basal forebrain cholinergic neurons in fear and extinction memory. Neurobiol Learn Mem 2016; 133:39-52. [PMID: 27264248 DOI: 10.1016/j.nlm.2016.06.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 05/26/2016] [Accepted: 06/02/2016] [Indexed: 12/30/2022]
Abstract
Cholinergic input to the neocortex, dorsal hippocampus (dHipp), and basolateral amygdala (BLA) is critical for neural function and synaptic plasticity in these brain regions. Synaptic plasticity in the neocortex, dHipp, ventral Hipp (vHipp), and BLA has also been implicated in fear and extinction memory. This finding raises the possibility that basal forebrain (BF) cholinergic neurons, the predominant source of acetylcholine in these brain regions, have an important role in mediating fear and extinction memory. While empirical studies support this hypothesis, there are interesting inconsistencies among these studies that raise questions about how best to define the role of BF cholinergic neurons in fear and extinction memory. Nucleus basalis magnocellularis (NBM) cholinergic neurons that project to the BLA are critical for fear memory and contextual fear extinction memory. NBM cholinergic neurons that project to the neocortex are critical for cued and contextual fear conditioned suppression, but are not critical for fear memory in other behavioral paradigms and in the inhibitory avoidance paradigm may even inhibit contextual fear memory formation. Medial septum and diagonal band of Broca cholinergic neurons are critical for contextual fear memory and acquisition of cued fear extinction. Thus, even though the results of previous studies suggest BF cholinergic neurons modulate fear and extinction memory, inconsistent findings among these studies necessitates more research to better define the neural circuits and molecular processes through which BF cholinergic neurons modulate fear and extinction memory. Furthermore, studies determining if BF cholinergic neurons can be manipulated in such a manner so as to treat excessive fear in anxiety disorders are needed.
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Affiliation(s)
- Dayan Knox
- Department of Psychological and Brain Sciences, Behavioral Neuroscience Program, University of Delaware, Newark, DE, United States.
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Nicastro TM, Greenwood BN. Central monoaminergic systems are a site of convergence of signals conveying the experience of exercise to brain circuits involved in cognition and emotional behavior. Curr Zool 2016; 62:293-306. [PMID: 29491917 PMCID: PMC5804240 DOI: 10.1093/cz/zow027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 02/11/2016] [Indexed: 01/04/2023] Open
Abstract
Physical activity can enhance cognitive function and increase resistance against deleterious effects of stress on mental health. Enhanced cognitive function and stress resistance produced by exercise are conserved among vertebrates, suggesting that ubiquitous mechanisms may underlie beneficial effects of exercise. In the current review, we summarize the beneficial effects of exercise on cognitive function and stress resistance and discuss central and peripheral signaling factors that may be critical for conferring the effects of physical activity to brain circuits involved in cognitive function and stress. Additionally, it is suggested that norepinephrine and serotonin, highly conserved monoamines that are sensitive to exercise and able to modulate behavior in multiple species, could represent a convergence between peripheral and central exercise signals that mediate the beneficial effects of exercise. Finally, we offer the novel hypothesis that thermoregulation during exercise could contribute to the emotional effects of exercise by activating a subset of temperature-sensitive serotonergic neurons in the dorsal raphe nucleus that convey anxiolytic and stress-protective signals to forebrain regions. Throughout the review, we discuss limitations to current approaches and offer strategies for future research in exercise neuroscience.
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Abstract
Fear memory is the best-studied form of memory. It was thoroughly investigated in the past 60 years mostly using two classical conditioning procedures (contextual fear conditioning and fear conditioning to a tone) and one instrumental procedure (one-trial inhibitory avoidance). Fear memory is formed in the hippocampus (contextual conditioning and inhibitory avoidance), in the basolateral amygdala (inhibitory avoidance), and in the lateral amygdala (conditioning to a tone). The circuitry involves, in addition, the pre- and infralimbic ventromedial prefrontal cortex, the central amygdala subnuclei, and the dentate gyrus. Fear learning models, notably inhibitory avoidance, have also been very useful for the analysis of the biochemical mechanisms of memory consolidation as a whole. These studies have capitalized on in vitro observations on long-term potentiation and other kinds of plasticity. The effect of a very large number of drugs on fear learning has been intensively studied, often as a prelude to the investigation of effects on anxiety. The extinction of fear learning involves to an extent a reversal of the flow of information in the mentioned structures and is used in the therapy of posttraumatic stress disorder and fear memories in general.
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Affiliation(s)
- Ivan Izquierdo
- National Institute of Translational Neuroscience, National Research Council of Brazil, and Memory Center, Brain Institute, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Cristiane R. G. Furini
- National Institute of Translational Neuroscience, National Research Council of Brazil, and Memory Center, Brain Institute, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Jociane C. Myskiw
- National Institute of Translational Neuroscience, National Research Council of Brazil, and Memory Center, Brain Institute, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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